Paper feeding device for a duplicating machine

ABSTRACT

A paper feeding device for a duplicating machine using a rolled paper as a copying sheet, having a plurality pairs of feed rollers, said pairs including intermittently paper feeding first rollers, second rollers rotating at lower speed than the first rollers and feeding out the paper a predetermined length at a time, third rollers lower than the second rollers and a cutter synchronously cutting the paper with said third rollers.

United States Patent 1191 1111 3,884,103 Namba May 20, 1975 1 PAPER FEEDING DEVICE FOR A 3.653.757 4/1972 Newcomb 83/205 x 3,727,499 4/l973 Boston r 83/205 DUPLKATING MACHINE 3.757.619 9/1973 Gianese 83/280 x [75] 1 Inventor: Yoshiharu Namba, Webster. NY.

[73] Assignee: Fuji Xerox Co., Ltd., Tokyo. Japan Primary Ewmmer Frank T Yost [22] Filed: Oct. 5, 1973 Attorney, Agent, or Firm-Gerald .l. Ferguson, Jr.; 21] Appl. 190.; 403,885 Meph Baker [30} Foreign Application Priority Data 57] ABSTRACT Oct. 5, 1972 Japan 47-994l7 I A paper feeding device for a duplicating machine [52] US. Cl. 83/156; 83/63; 83/205; using 3 rolled paper as 3 copying Sheet having a 83/280? 83/649 rality pairs of feed rollers, said pairs including inter- [5 l] Int. (J B26d 5/20 mittently paper f di fi rollers second rollers Fleld of Search 83/]56- tating at lower speed than the first rollers and feeding 83/649- 64 out the paper a predetermined length at a time. third rollers lower than the second rollers and a cutter syn- References C'ted chronously cutting the paper with said third rollers.

UNITED STATES PATENTS l 625,403 4/ I927 Stevens 83/280 X 3 Claims, 7 Drawing Figures PAIENIEBMA Z W 3,884,103

' ,SHEET1UF 4 FIG. I

HQTENTEB HAYZO IUFS SHEET 2 OF 4 PAPER FEEDING DEVICE FOR A DUPLICATING MACHINE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a paper feeding device for a duplicating machine, particularly to a paper feeding device wherein a cutter, operating in synchronization with paper feeding movement of feed rollers, is positioned between a set of paper feed rollers and a set of feed rollers for advancing a paper sheet to a copying stage and said cutter is arranged to cut paper from a roll into a sheet of predetermined length as the roll paper between the two sets of feed rollers forms a loop or droop due to rotation rate differential therebetween, and thereby adverse effects of cutting that would otherwise be imposed on copying step may be effectively prevented.

2. Description of the Prior Art With recent development of high-speed duplicating machines, the previous practice of using copying p'apers already cut into a predetermined size is being gradually replaced by use of rolled paper to be cut to predetermined size during the copying process. Use of rolled paper requires that a cutting stage be incorporated into the apparatus. In the case of prior-art devices wherein a paper sheet cut in the cutting stage stops momentarily at an exposing position to receive light rays before entering into a fixing stage, the momentary halting of the copying sheet for exposure purposes becomes a bar to obtaining an increased operation speed of the copying machines. Even when the copying sheet is exposed to light rays without halting the sheet travel (that is, by synchronizing the sheet feeding speed with the scanning speed during exposure), the impact that results from cutting the paper roll adversely affects the copying step, causing such defects in the formed image as aberration. One method for preventing this is to perform cutting of roll paper only after copying, but the drawback with this method is that it requires an additional device for detecting or determining the cutting position from the formed image, making the apparatus too bulky and too costly to suit practical use.

SUMMARY OF THE INVENTION The object of the current invention is to overcome such shortcomings of the prior-art devices as mentioned above and to provide a suitable device for increasing operation speed of duplicating machines by positioning a cutter between paper feed rollers and feed rollers which are adapted to transfer a paper sheet to a copying stage, operation of the cutter being synchronized to the paper feeding motion, arranging said cutter to cut the roll paper into a predetermined size when there is formed a loop of the roll paper due to the rotation rate differential between the two sets of feed rollers, thereby absorbing the impact of cutting at said paper loop to protect the copying step from any adverse effect of cutting.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a diagrammatic view of the entire duplicating machine;

FIG. 2 is a perspective view showing in detail a machine portion for di'iving the second feed rollers;

FIG. 3 is a side view of the portion in FIG. 2;

FIG. 4 is a perspective view showing in detail a cutter portion;

FIG. 5 is a side view of the cutter portion in FIG. 4;

FIG. 6 is an electric circuit diagram of a control systern;

FIG. 7 is a time chart indicating timing of various parts.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of this invention is hereinafter described in detail with reference to the drawings.

FIG. 1 shows a xerographic duplicating machine with paper feeding device A according to this invention. The circumferential surface of a xerograph drum 1 coated with photoconductive material is charged by a charger 2, and light rays from the light source 3 reflected from a master sheet 4 to be copied are projected to the cylindrical surface of the drum 1 to dissipate charges in an image pattern, thereby forming on the cylindrical surface of the drum 1 a latent image identical to the master sheet 4. This latent image is developed in the next developing step to a visible image which is transferred onto copying sheet a. At the same time, toner remaining on the cylindrical surface of xerograph drum 1 is removed by a cleaning device 6 while the copying sheet a with its transferred image is conveyed by a feeding mechanism 7 to a fixer 8 by which the image is permanently fixed. The structure of the feeding device A is as follows. Paper roll 11 is detachably mounted underneath a main body 10 of the duplicating machine with the leading edge of the rolled paper 11 inserted through the first feed rollers 12, through the second feed rollers 13 which are spaced apart from the first feed rollers 12, and through the third feed rollers 14 which serve to feed a paper sheet to the xerograph drum 1. Between the first feed rollers 12 and second feed rollers 13 is positioned a microswitch 15 for detecting tension of the roll paper 11. The ON-OFF state of microswitch 15 regulates intermittent rotation of the first feed rollers 12. In other words, while the roll paper 11 is stretched and tensioned, the microswitch 15 is ON and a clutch (not shown) of the mechanism (not shown) for driving the first feed rollers 12 is engaged to rotate the first feed roller 12 at a rate greater than that of the second feed rollers 13 thereby causing the roll paper 11 to form a loop or droop between the first feed rollers 12 and the second feed rollers 13. When the roll paper 11 droops, the microswitch 15 is cut off and rotation of the first feed rollers 12 halts. By repetition of the abovenoted sequence of operation, slippage between second feed rollers 13 and roll paper 11 is kept at a minimum. Also said second feed rollers 13 are arranged to be driven through a spring clutch 16 shown in FIG. 2 Input shaft 17 of the spring clutch 16 always turns ir the direction shown by arrow x, while output shaft 18 is drivingly linked together with a cam plate 19 having a plurality of equally spaced apertures 19b to a driving shaft 13a of the second feed rollers 13. Between the input shaft 17 and output shaft 18 is linkedly positionet a collar 20 with a lobe (not shown) formed there around. When one end of an interposer 21 engage: with said lobe of the collar 20, the spring clutch 16 i: disengaged. Likewise the spring clutch 16 is connect edly engaged when the lobe and interposer 21 are dis engaged. The interposer 21 is held at the mid portioi by a pivot 21a for free rotational movement. The basi end of the interposer 21 is in engagement with one end of a plunger 22a of a solenoid 22. One end of the interposer 21 is also engaged to one end of another interposer 23. A central portion of the interposer 23 is pivotally supported, in a position underneath the spring clutch 16, by a pivot 24 while the other end of the interposer 23 engages with one end of rod 27 extending out from the interposer 26 of the spring clutch 25 for the cutter, spring clutch 16 being positioned on the other side of the interposer 21. The interposer 26 is pivotally supported at its upper edge portion for free vibrating motion of the lower edge portion, with the central portion having an aperture 26a bored through to receive for loose fitting, base end portion of said rod 27, the pointed end portion of rod 27 extending out toward the spring clutch 16. At the lower surface in the mid portion of the rod 27 is formed a recess 27a which fittingly receives one end of a link 28. The link 28 is pivotally supported at the mid portion thereof for free rotational movement. The other end of the link 28 slidingly engages with the outer surface of said cam plate 19. R- tatingly driven by projections 19a which are formed at uniform intervals around prephery of cam plate 19, the link 28 urges said rod 27 to move in the direction indicated by arrow y. Movement of the rod 27 in the direction y rotates the lower edge portion of the interposer 26 of the cutter spring clutch 25 for the cutter, to disengage said interposer 26 from the collar 29 of the cutter spring clutch 25, thereby actuating the cutter 30. The cutter 30 is positioned between the second feed rollers 13 and third feed rollers 14, as shown in FIG. 1, and is constructed as shown in FIG. 4. At one end of the output shaft 31 of the cutter clutch 25 is fixedly secured a disc 32. To an eccentric position thereof is pivotally secured one end of a link 33. The other end of the link 33 extends slantedly upward and pivotally couples with an upper end of a substantially L-shaped crank 34. To the lower end of the crank 34 is fixedly secured the end portion of the rotary cutter 30a, which is designed to rotate back and forth around the rotary shaft 30b of the rotary cutter 30a in response to rotation of said output shaft 31. Slantingly upward of rotary cutter 30a is provided a fixed cutter 300 with a blade so positioned as to align with the blade of rotary cutter 30a as rotary cutter 30a moves, severing paper sheet 11 fed between the two cutters.

With reference to FIG. 6 the electric circuit of the duplicating machine with above-described construction is now explained in connection with the machines operation. The light rays from the light source 3 reflected from master sheet 4 charges and produces a latent image on the outer cylindrical surface of the xerograph drum 1 as the drum 1 rotates, which latent image is subsequently developed in a developing section into a visible image. Simultaneously, the leading edge of the roll paper 11 travels, driven by the rotation of the first feed rollers 12 from the paper feeding device A to the second feed rollers 13 and to the third feed rollers 14, in the order just mentioned, and then to the lower part of the xerograph drum 1. The third feed rollers 14 always revolve at a lower rate than the second feed rollers 13, causing the roll paper 11 to sag in the form of a loop between the second feed rollers 13 and third feed rollers 14 as indicated by a broken line in FIG. 1, which loop absorbs the impact which is imposed on the roll paper 11 by the cutter 30, to be described next, to prevent adverse effects on copying. The cutter 30 is controlled in the following manner to cut the roll paper 11 for supplying copying paper a of a predetermined length.

When a print switch SW1 is turned on, a signal is produced at the output terminal of NAND gate 1 to set the terminal 41 of NAND gate II at the level 1 or in the l state. The terminal 42 of the NAND gate II is for reset purposes. When power supply (not shown) is switched on, a negative pulse is dispatched from the terminal 42 through the NAND gate II and inverter [11b to reset flipflop counters IV-VIII. The terminal 43, for synchronizing timing, drops to the level 0 or the 0 state only when a predetermined count, i.e., a number of apertures formed on disc the 19 is counted, and is otherwise set at the 1 level. Before the print switch SW1 is switched on, the terminals 42, 43 of the NAND gate II are at the level 1, and when print switch SW1 is turned on a signal of the level 1 is received by terminal 41 to set the output terminal 44 at the level 0. Then the level is reversed by an inverter IIIb to actuate a thyristor (SCR) and to energize the solenoid 22. With energization of the solenoid 22, the plunger 22a is withdrawn to rotate the interposer 21 around the axial shaft 21a, which disengages interposer 21 from the lobe around the collar 20 of the spring clutch 16 whereupon cam plate 19 starts rotation along with the second feed rollers 13. Simultaneously the interposer 23 is set in rotation by the interposer 21 to upwardly press one end of the rod 27. This causes the rod 27 to disengage from the link 28, a follower of the cam plate 19. Also a photocell or a similar detector PC (see FIG. 6) which is closely positioned to the cam plate 19 counts apertures 19b formed through the cam plate 19. Signals from the detector PC pass throuogh the transistor Tr2 to one-shot multivibrator O.M.V., actuating the same to produce a single pulse. The pulse in turn actuates flip-flop counters lV-VIII. The flip-flop counters IV-VIII in response to signals of 2 to 2 respectively emit signals of the level 1, which in combination with selection of the switches SW2, SW3 and SW4 act to set the output of one of the NAND gates IXa-IXc at the level 0. For example, if the switch SW2 for A4 size copies is selected, only the ter- 4 minal 2 of the NAND gate IXa is held at the level 1 while the terminals 5 and 10 of the NAND gates IX!) and IXc are held at the level 0 potential. As the cam plate 19 continues to rotate and when it has completed 2.25 revolutions, i.e., when the second feed rollers 13 have advanced roll paper 11 by a length corresponding to the A4 size, the one-shot multivibrator O.M.V. emits a ninth pulse and the flip-flop counter IV for 2 and the flip-flop counter VlI for 2 respectively send the level 1 signals to set the potential of the input terminals 1 and 13 of the NAND gate IXa at the level 1, whereupon all input terminals of the NAND gate IXa become the level 1 to set the output terminal 12 at the 0 level. This sets the input terminals 43 of the NAND gate II to the level 0 and hence the output terminal 44 to the level 1. The signal is inverted to the level 0 passing through the inverter Illa, which turns off SCR to de-energize the solenoid 22. A level 1 signal from the output terminal 44 becomes a level 0 signal passing through inverter IIIb to reset the flip-flop counters IV-VIII. With deenergization of the solenoid 22, the interposer 21 engages with flie lobe around collar 20 to disengage the spring clutch 16, and thereby to halt rotation of the second feed rollers 13 and thus feeding of the roll paper 1 1. After the plunger 22a is released from solenoid 22 and the interposer 21 is brought in contact with the surface of the collar 20, the'cam 19 continues to rotate a while until the interposer 21 actually engages with the lobe of the collar 20. With-release of the plunger 22a, on the other hand, the link 28 is returned to the original position to engage with the rod 27. Under these conditions, the link 28, by the urge of the projection 19a formed around the cam 19, presses the rod 27 to move in the direction of arrow Y. This movement of the rod 27 releases the interposer 25 of the cutter spring clutch 25 from the lobe (not shown) formed around the collar 29 of said spring clutch 25 to actuate the cutter 30. That is, by engagement of the cutter spring clutch 25, the disc 32 through the link 33 drivingly rotate the rotary cutter 30a back and forth in the direction of the arrow shown in FIG. 4 to cut in a predetermined size with the fixed cutter 30c the roll paper 11 positioned between the two cutters. On the collar 29 of the cutter spring clutch 25 is formed a lobe. As soon as the rod 27 is pressed to move in the direction of the arrow Y by the link 28 shown in FIG. 2 and the interposer 26-is released from engagement, rotation of the cam 19 stops and the rod 27 becomes free, released from the link 28. Under these conditions, the interposer 26 is urged by the spring (not shown) to pressingly contact with the surface of the collar 29 of the cutter spring clutch 25, thereby reengaging with the lobe 29 of said collar 29 after one revolution of collar 29 to disengage clutch 25. Thus reciprocating rotation of the rotary cutter 30a of the cutter 30 terminates after one cycle and preparation is made for cutting the next paper sheet.

The operation thus described is illustrated in the time chart of FIG. 7. Taking an actual case of operation for simplicity of description, the number of lobes around the collar of the spring clutch l6 and the number of projections 19a of the cam plate 19, the number of apertures 19b formed on the cam plate 19 are assumed to be four, respectively. Thus at the ninth lobe, i.e., 2.25 revolutions, second feed rollers 13 advance the paper sheet by a distance corresponding to the A4 size. Now supposing that selection was made to feed A4 paper, after passing the eighth lobe, the circuit to be described later emits a signal at the ninth aperture 19b on cam plate 19 to de-energize the solenoid 22. By the time an approximately 20 revolution was made after emission of the signal, the solenoid 22 is d e-energized. Then after a further rotation of 60, the interposer 21 engages with the ninth lobe and second feed rollers 13 stops and so does roll paper 11. Slightly before engagement of the interposer 21 to the ninth lobe of collar 20, the cutter spring clutch engages to actuate the rotary cutter a of the cutter 30. After the second feed roller 13 stops, the roll paper 11 is kept feeding by the third feed rollers 14 thereby reducing the loop of the roll paper 11 between the third feed rollers 14 and the second feed rollers 13. Before the loop fully disappears, however, cutting of the paper sheet completes.

Description given so far assumes selection of A4 size paper, but by making proper selections of the number of the apertures 19b on the cam 19 and the number of counters, many sizes of copy paper may be provided, with accordingly varied widths of the roll paper 11.

As heretofore described in detail adverse effects of cutting on copying step such as aberration of formed image are reliably prevented by causing roll paper to form a loop between the second feed rollers and the third feed rollers by a rotation rate differential therebetween, cutting the paper to yield a copying sheet of predetermined size by a cutter positioned between the second and the third feed rollers, and thereby absorbing the impact of cutting on the paper by said loop. Also utilization of rolled paper facilitates speed-up of duplicating machine operation, and simultaneous cutting of the paper during copying eliminates the need for a bulky apparatus for determing cutting positions as required for those which cut the paper after copying, making it possible to supply small and low priced duplicating machines.

What is claimed is:

l. A paper feeding device for a duplicating machine using a paper roll as a copying sheet, said feeding device comprising first feed rollers for intermittently feeding said paper roll, second feed rollers for receiving said paper roll from said first feed rollers and for delivering a predetermined length of said paper roll, said second feed rollers rotating at a slower rate than said first feed rollers, third feed rollers for slackening said roll paper between said second feed rollers and said third feed rollers by a rotation rate differential therebetween, said third feed rollers continuously rotating at a slower rate than said second feed rollers, and a cutter for cutting said paper roll to a said predetermined length, said cutter positioned between said second feed rollers and said third feed rollers, the timing of said cutting being synchronized to that of movement suspension of said second feed rollers.

2. A paper feeding device for use in a duplicating machine or the like, said feeding device comprising at least one pair of feed rollers for receiving said copy means for delivering a predetermined length of copy paper from said one feed roller pair;

another feed roller pair for receiving the copy paper from the one feed roller pair, said another feed roller pair continuously rotating at a speed less than that of said one feed roller pair to form a loop of said copy paper between said one and another roller pairs;

cutting means disposed between said one and another feed roller pairs for cutting said copy paper to said predetermined length; and

means for stopping said one roller pair after said predetermined length of copy paper has been delivered thereby and for actuating said cutting means.

to cut said predetermined length of copy paper before another roller pair removes said loop so that said loop absorbs the impact of said cutting means on the copy paper to thereby lessen the affect of the cutting step on the operation of the duplicating machine or the like.

3. A paper feeding device for use in a duplicating machine or the like, said feeding device comprising first feed rollers for feeding a continuous roll of copy second feed rollers for receiving said copy paper from said first rollers;

means for intermittently increasing the speed of said first feed rollers with respect to said second feed rollers to form a first loop of said copy paper therebetween to lessen slippage between said second feed follers and said copy paper;

means for delivering a predetermined length of copy paper from said second feed rollers;

predetermined length of copy paper has been delivered thereby and for actuating said cutting means to cut said predetermined length of copy paper before the third roller pair removes said second loop so that said second loop absorbs the impact of said cutting means on the copy paper to thereby lessen the affect of the cutting step on the operation of the duplicating machine or the like. 

1. A paper feeding device for a duplicating machine using a paper roll as a copying sheet, said feeding device comprising first feed rollers for intermittently feeding said paper roll, second feed rollers for receiving said paper roll from said first feed rollers and for delivering a predetermined length of said paper roll, said second feed rollers rotating at a slower rate than saiD first feed rollers, third feed rollers for slackening said roll paper between said second feed rollers and said third feed rollers by a rotation rate differential therebetween, said third feed rollers continuously rotating at a slower rate than said second feed rollers, and a cutter for cutting said paper roll to a said predetermined length, said cutter positioned between said second feed rollers and said third feed rollers, the timing of said cutting being synchronized to that of movement suspension of said second feed rollers.
 2. A paper feeding device for use in a duplicating machine or the like, said feeding device comprising at least one pair of feed rollers for receiving said copy paper; means for delivering a predetermined length of copy paper from said one feed roller pair; another feed roller pair for receiving the copy paper from the one feed roller pair, said another feed roller pair continuously rotating at a speed less than that of said one feed roller pair to form a loop of said copy paper between said one and another roller pairs; cutting means disposed between said one and another feed roller pairs for cutting said copy paper to said predetermined length; and means for stopping said one roller pair after said predetermined length of copy paper has been delivered thereby and for actuating said cutting means to cut said predetermined length of copy paper before another roller pair removes said loop so that said loop absorbs the impact of said cutting means on the copy paper to thereby lessen the affect of the cutting step on the operation of the duplicating machine or the like.
 3. A paper feeding device for use in a duplicating machine or the like, said feeding device comprising first feed rollers for feeding a continuous roll of copy paper; second feed rollers for receiving said copy paper from said first rollers; means for intermittently increasing the speed of said first feed rollers with respect to said second feed rollers to form a first loop of said copy paper therebetween to lessen slippage between said second feed follers and said copy paper; means for delivering a predetermined length of copy paper from said second feed rollers; third feed rollers for receiving the copy paper from the second feed rollers, said third feed rollers continuously rotating at a speed less than that of said second feed rollers to form a second loop of said copy paper between said second and third roller pairs; cutting means disposed between said second and third feed rollers for cutting said copy paper to said predetermined length; and means for stopping said second roller pair after said predetermined length of copy paper has been delivered thereby and for actuating said cutting means to cut said predetermined length of copy paper before the third roller pair removes said second loop so that said second loop absorbs the impact of said cutting means on the copy paper to thereby lessen the affect of the cutting step on the operation of the duplicating machine or the like. 